U.S. patent application number 12/503146 was filed with the patent office on 2011-01-20 for preparing a pass-through for an occupant compartment - engine compartment ground block.
This patent application is currently assigned to International Truck Intellectual Property Company, LLC. Invention is credited to Stephen Burns.
Application Number | 20110011526 12/503146 |
Document ID | / |
Family ID | 43382923 |
Filed Date | 2011-01-20 |
United States Patent
Application |
20110011526 |
Kind Code |
A1 |
Burns; Stephen |
January 20, 2011 |
Preparing A Pass-Through For An Occupant Compartment - Engine
Compartment Ground Block
Abstract
A special patch is adhered to the bare metal of a dash panel in
covering relation to one or more pass-through holes and their
margins before a truck cab is primed and painted. After painting, a
cover of the patch is peeled off to expose an electrically
conductive medium that remains adhered to the bare metal. A ground
block is mounted on the dash panel with a stud passing through a
pass-through hole. The electrically conductive medium establishes
conductivity of the body of the ground block to the dash panel.
Inventors: |
Burns; Stephen; (Huntertown,
IN) |
Correspondence
Address: |
International Truck Intellectual Property Company,
4201 WINFIELD ROAD
WARRENVILLE
IL
60555
US
|
Assignee: |
International Truck Intellectual
Property Company, LLC
Warrenville
IL
|
Family ID: |
43382923 |
Appl. No.: |
12/503146 |
Filed: |
July 15, 2009 |
Current U.S.
Class: |
156/247 |
Current CPC
Class: |
Y10T 156/11 20150115;
H02G 3/22 20130101; B60R 16/0215 20130101 |
Class at
Publication: |
156/247 |
International
Class: |
B29C 65/48 20060101
B29C065/48 |
Claims
1. A method for preparing a pass-through in an electrically
conductive structural panel of a motor vehicle that separates an
engine compartment from an occupant compartment for subsequent
mounting of a ground block on the panel to provide a ground to
which engine compartment circuits of an electrical system of the
vehicle can be connected and to which occupant compartment circuits
of the electrical system can be connected, the method comprising:
adhering a patch to bare metal of the panel in covering relation to
one or more pass-through holes in the panel prior to applying one
or more electrically non-conductive coatings to the panel; and
after the one or more coatings have been applied and dried,
removing an outer cover of the patch to expose an electrically
conductive medium of the patch that remains in covering relation to
bare metal forming a margin of the one or more through-holes.
2. A method as set forth in claim 1 wherein the step of adhering
the patch to bare metal of the panel in covering relation to one or
more pass-through-holes comprises adhering a portion of the cover
to the bare metal.
3. A method as set forth in claim 2 wherein the step of adhering
the patch to bare metal of the panel in covering relation to one or
more pass-through-holes comprises adhering also includes adhering
the electrically conductive medium.
4. A method as set forth in claim 1 wherein the step of adhering
the patch to bare metal of the panel in covering relation to one or
more pass-through-holes comprises adhering the electrically
conductive medium without adhering the patch.
5. A method as set forth in claim 1 further including the step of
mounting a ground block on the dash panel by passing a stud of the
ground block through a pass-through hole, disposing a body of the
ground block against the exposed electrically conductive medium,
and fastening the ground block to the dash panel.
6. A method for preparing a pass-through in an electrically
conductive structural panel of a motor vehicle that separates an
engine compartment from an occupant compartment for subsequent
mounting of a ground block on the panel to provide a ground to
which engine compartment circuits of an electrical system of the
vehicle can be connected and to which occupant compartment circuits
of the electrical system can be connected, the method comprising:
adhering the outer margin of a patch cover to bare metal of the
panel forming a margin of one or more pass-through holes in the
panel prior to applying one or more electrically non-conductive
coatings to the panel to cause an electrically conductive medium
bounded by the outer margin of the patch cover to be placed in
covering relation to at least a portion of the margin of the one or
more pass-through holes; and after the one or more coatings have
been applied and dried, removing the patch cover to expose the
electrically conductive medium.
7. A method as set forth in claim 6 further including the step of
mounting a ground block on the dash panel by passing a stud of the
ground block through a pass-through hole, disposing a body of the
ground block against the exposed electrically conductive medium,
and fastening the ground block to the dash panel.
8. A method for preparing a pass-through in an electrically
conductive structural panel of a motor vehicle that separates an
engine compartment from an occupant compartment for subsequent
mounting of a ground block on the panel to provide a ground to
which engine compartment circuits of an electrical system of the
vehicle can be connected and to which occupant compartment circuits
of the electrical system can be connected, the method comprising:
adhering at least one electrically conductive pad on the inner
surface of a patch cover to bare metal of the panel forming a
margin of one or more pass-through holes in the panel prior to
applying one or more electrically non-conductive coatings to the
panel; and after the one or more coatings have been applied and
dried, removing the patch cover to expose the at least one
electrically conductive pad.
9. A method as set forth in claim 8 further including the step of
mounting a ground block on the dash panel by passing a stud of the
ground block through a pass-through hole, disposing a body of the
ground block against the exposed electrically conductive medium,
and fastening the ground block to the dash panel.
10. A method as set forth in claim 8 including adhering a portion
of the cover to bare metal of the panel.
11. A method as set forth in claim 10 further including the step of
mounting a ground block on the dash panel by passing a stud of the
ground block through a pass-through hole, disposing a body of the
ground block against the exposed electrically conductive medium,
and fastening the ground block to the dash panel.
Description
FIELD OF THE INVENTION
[0001] This invention relates generally to motor vehicle electrical
systems, and in particular it relates to the grounding of engine
compartment circuits and occupant compartment circuits at a common
ground block that mounts on a dash panel separating the two
compartments from each other.
BACKGROUND OF THE INVENTION
[0002] Structural components of a motor vehicle that are electrical
conductors, such as metal of the body and the chassis frame, form
the electrical ground for the vehicle's electrical system. Motor
vehicles that operate on roads and highways typically have an
occupant compartment, where the driver and any passenger or
passengers sit, and in front of the occupant compartment, an engine
compartment for housing the engine that propels the vehicle. In a
large truck, the occupant compartment is commonly called the
cab.
[0003] A dash panel that is part of a truck cab separates the cab
interior from the engine compartment. A known practice for
grounding at least some engine compartment circuits and at least
some occupant compartment circuits to the vehicle's ground
comprises grounding the circuits through a ground block that is
mounted on the dash panel at a pass-through.
[0004] A typical ground block has a base that is disposed against
the dash panel on either the engine compartment side or the cab
side and fastened to the dash panel. One or more studs project from
the base, either toward the engine compartment or toward the
occupant compartment. If the base is disposed against the cab side
of the dash panel, one or more studs project through one or more
respective holes in the dash panel and into the engine compartment.
If the base is disposed against the engine compartment side of the
dash panel, the one or more studs project through one or more holes
in the dash panel and into the cab interior. The ground block may
also comprise one or more studs that project away from a surface of
the base that is opposite the surface that is disposed against the
dash panel.
[0005] The terminal of one or more electrical ground wires or
ground cables is located to a stud of the ground block and a nut on
the stud is tightened down against the one or more terminals
thereby grounding the wires and cables to the ground block. Where
studs are present on both engine compartment and cab sides, both
cab circuit ground wires or cables and engine circuit ground wires
or cables can be connected in common at the ground block.
[0006] Because many body panels of a truck cab, like the dash
panel, are steel, and because steel is an electrical conductor, the
contact between the dash panel and the mounted ground block grounds
both engine compartment and cab grounds to the cab body.
[0007] Because it is desirable that good electrical contact be
established between the ground block and the dash panel, and
because certain truck cabs are pre-painted before the ground block
is mounted on the dash, it is necessary that the paint and the
primer or undercoat be removed from the area of the dash
surrounding the pass-through hole, or holes, for a grounding block
stud, or studs, before the ground block is mounted.
[0008] This stripping of insulated matter from the underlying
conductor is typically performed by a mechanical action on an
assembly line, such as by applying a wire wheel that is being spun
by a power tool to the painted surface to abrade the paint and the
primer or undercoat until bare metal is exposed.
[0009] That procedure however creates dust and exposes the bare
metal to possible rusting. Because it is also difficult to control
the amount of paint and undercoat being stripped, the process is to
some degree inherently inconsistent from truck to truck.
[0010] The inventor believes that the process of assuring good
conductivity between the ground block and the dash panel can be
greatly improved by using a different process that doesn't involve
removal of the paint and undercoat by mechanical abrasion.
SUMMARY OF THE INVENTION
[0011] One disclosed embodiment of the inventive process comprises
applying a special patch to the bare metal of the dash panel in
covering relation to one or more pass-through holes and their
margins before the cab is primed and painted. The patch comprises a
strippable cover having inner and outer surfaces. The outer
perimeter margin of the inner surface contains an adhesive for
adhering to the dash panel. Dielectric grease and/or conductive
grease is present on a zone of the inner surface of the cover whose
perimeter is bounded by the adhesive.
[0012] After the cab has been primed and painted, and the paint has
dried, primer and paint cover the patch. The edge of a tool is
inserted into the paint and primer at the edge of the patch cover
and manipulated beneath the margin of the cover sufficiently to
enable further manipulation to pry the cover edge away from the
dash panel. The edge can then be grasped and the cover peeled
off.
[0013] While the cover was in place on the dash panel, the grease
was in contact with the bare metal surrounding the pass-through
hole, or holes. The grease has sufficient tenacity with the bare
metal that a layer of grease remains on the bare metal as the cover
is being peeled off.
[0014] With the patch cover having been removed, the ground block
is mounted on the dash panel by aligning one or more of its studs
with the one or more pass-through holes in the dash panel and
passing the studs through the holes to place the body of the ground
block against the residual grease on the dash panel and then
fastening the ground block to the dash panel, such as by passing
screws through holes in the ground block body and tightening them
in holes in the dash panel to force the grease to be squeezed
between the ground block and the dash panel. Any excess grease that
is squeezed out beyond the base of the ground block can be wiped
away if necessary. The grease establishes electrical contact
between the ground block and the bare metal of the dash panel.
[0015] With the ground block having been mounted and grounded to
the cab body at the dash panel, the engine and circuit grounds can
be connected to the ground block.
[0016] Another disclosed embodiment of the inventive process
comprises applying a second type of special patch to the bare metal
of the dash panel in covering relation to one or more pass-through
holes and their margins before the cab is primed and painted. This
second type of patch also comprises a strippable cover having inner
and outer surfaces. The entire inner surface of the cover is
covered by an electrically conductive pad that adheres the patch to
the bare metal of the dash panel, except where the pad has holes
for registering with the pass-through holes.
[0017] After the cab has been primed and painted, and the paint has
dried, the edge of a tool is inserted into the paint and primer at
the edge of the patch cover and manipulated beneath the margin of
the cover sufficiently to enable further manipulation to pry the
cover edge away from the dash panel. The edge can then be grasped
and the cover peeled off. The electrically conductive pad has less
adherence to the cover than to the bare metal of the dash panel,
and so it remains adhered to the dash panel after the cover has
been peeled off.
[0018] With the cover having been removed, the ground block is
mounted on the dash panel by aligning one or more of its studs with
the one or more pass-through holes in the dash panel (the holes are
not covered by the conductive pad) and passing the studs through
the pass-through holes to place the body of the ground block
against the conductive pad and then fastening the ground block to
the dash panel, such as by passing screws through holes in the
ground block body and tightening them in holes in the dash panel to
force the conductive pad to be squeezed between the ground block
and the dash panel and establish electrical contact between the
ground block and the bare metal of the dash panel.
[0019] With the ground block having been mounted and grounded to
the cab body at the dash panel, the engine and circuit grounds can
be connected to the ground block.
[0020] Still another embodiment of the inventive process comprises
applying a third type of special patch to the bare metal of the
dash panel in covering relation to one or more pass-through holes
and their margins before the cab is primed and painted. This third
type of patch also comprises a strippable cover having inner and
outer surfaces. The perimeter margin of the inner surface contains
an adhesive for adhering to the dash panel. The dielectric grease
and/or conductive grease of the first type of patch is replaced by
an electrically conductive pad, or pads, that adhere to the bare
metal of the dash panel.
[0021] After the cab has been primed and painted, and the paint has
dried, the edge of a tool is inserted into the paint and primer at
the edge of the patch cover and manipulated beneath the margin of
the cover sufficiently to enable further manipulation to pry the
cover edge away from the dash panel. The edge can then be grasped
and the cover peeled off. The electrically conductive pad, or pads,
have less adherence to the cover than they do to the bare metal of
the dash panel, and so they remain adhered to the dash panel after
the cover has been peeled off.
[0022] With the cover having been removed, the ground block is
mounted on the dash panel by aligning one or more of its studs with
the one or more pass-through holes in the dash panel (the holes are
not covered by the conductive pad or pads) and passing the studs
through the pass-through holes to place the body of the ground
block against the conductive tape and then fastening the ground
block to the dash panel, such as by passing screws through holes in
the ground block body and tightening them in holes in the dash
panel to force the conductive pad or pads to be squeezed between
the ground block and the dash panel. The pad or pads establish
electrical contact between the ground block and the bare metal of
the dash panel.
[0023] With the ground block having been mounted and grounded to
the cab body at the dash panel, the engine and circuit grounds can
be connected to the ground block.
[0024] The foregoing, along with further features and advantages of
the invention, will be seen in the following disclosure of a
presently preferred embodiment of the invention depicting the best
mode contemplated at this time for carrying out the invention. This
specification includes drawings, now briefly described as
follows.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] FIG. 1 is an elevation view of a portion of a truck dash
panel at a pass-through.
[0026] FIG. 1A is a view similar to FIG. 1 showing a primed and
painted dash panel from which the paint and primer have been
abraded to expose the underlying bare metal at the
pass-through.
[0027] FIG. 2 is a view in the same direction as FIG. 1 showing one
embodiment of special patch in place over the pass-through, in
accordance with principles of the invention.
[0028] FIG. 3 is a view in the same direction as FIG. 1 showing
another embodiment of special patch in place over the pass-through,
in accordance with principles of the invention.
[0029] FIG. 4 is a side elevation view partly in cross section
through the pass-through with a special patch applied to the dash
panel and its cover in the process of being peeled off.
[0030] FIG. 5 is a perspective view of a ground block that is to be
mounted on the dash panel at the pass-through.
[0031] FIG. 6 is a front elevation view of the ground block of FIG.
5.
[0032] FIG. 7 is a side elevation view of the ground block of FIG.
5.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0033] FIG. 1 shows a truck dash panel 10 in which the pass-through
comprises two circular holes 12, 14 of equal diameters centered on
an imaginary vertical line. Dash panel 10 separates the engine
compartment from the interior occupant compartment of the truck
cab. FIG. 1A shows another dash panel that had been primed and
painted, but with the paint and primer have been abraded to expose
the underlying bare metal (reference numeral 17) around the
pass-through holes 12, 14. FIG. 1A has been marked "prior art"
solely because it is representative of the prior process described
earlier. As can be seen, the abrasion process can leave an
irregular bare metal area 17.
[0034] FIG. 2 is representative of a special patch 16 having been
applied to the bare metal of dash panel 10 in covering relation to
holes 12, 14 and their margins before the cab is primed and
painted. Patch 16 comprises a strippable cover 18 having inner and
outer surfaces. The outer perimeter margin of the inner surface
contains an adhesive that adheres patch 16 to the bare metal of
dash panel 10. The adhesive bounds a zone of the inner surface of
the cover covered by dielectric grease and/or conductive grease.
That zone is defined by two circular areas 20, 22.
[0035] After the cab has been primed and painted, and the paint has
dried, primer and paint are covering the patch. The edge of a tool
(not shown) is inserted into the paint and primer at the edge of
the patch cover and manipulated beneath the margin of cover 18
sufficiently to enable further manipulation to pry the cover edge
away from dash panel 10. The edge can then be grasped and the cover
peeled off.
[0036] The grease has sufficient tenacity with the bare metal of
the dash panel that a layer of grease remains on the bare metal as
cover 18 is being peeled off. After the cover has been removed, a
ground block 24, shown in FIGS. 5-7, is mounted on dash panel
10.
[0037] Ground block 24 comprises a base, or body, 26 and multiple
studs 28, 30, 32, 34. Studs 28 and 30 project from opposite faces
of a circular disc 36 that is fit to a hole in base 26. Studs 32
and 34 project from opposite faces of a circular disc 38 that is
fit to another hole in base 26.
[0038] Ground block 24 can be mounted to dash panel 10 on either
the engine compartment side or the cab side. Assuming the mounting
is on the cab side, studs 30, 34 are aligned with
pass-through-holes 12, 14 and passed through the holes to place
body 26 against the residual grease on the dash panel. The ground
block is then fastened to the dash panel by passing screws (not
shown) through holes 40 in discs 36, 38 and tightening them in
holes in the dash panel to force the grease to be squeezed between
the ground block and the dash panel. Any excess grease that is
squeezed out beyond the base of the ground block can be wiped away
if necessary. The grease establishes electrical contact between the
ground block and the bare metal of the dash panel. Engine and cab
circuit grounds (not shown) can then be placed in association with
the respective studs and fastened in placed.
[0039] FIGS. 3 and 4 show another embodiment of special patch 16
that has a strippable cover 18 having inner and outer surfaces 181
and 180. The entirety of inner surface 181 is covered by an
electrically conductive pad 42 that adheres the patch to the bare
metal of the dash panel, except where the pad has holes 44, 46 for
registering with the pass-through holes 12, 14. FIGS. 3 and 4 show
patch 16 adhered to the bare metal of dash panel 10 by adhesive on
pad 42.
[0040] To remove cover 18, a tool (not shown) is manipulated
beneath the margin of the cover sufficiently to enable further
manipulation to pry the cover edge away from the dash panel, as
shown at the top of FIG. 4. The edge can then be grasped and the
cover peeled completely off The electrically conductive pad 42 is
adhered to the dash panel with greater adherence than that of the
cover to the pad, allowing the cover to be peeled off while leaving
the pad adhered to the dash panel.
[0041] With the cover having been removed, the ground block is
mounted on the dash panel is the same way as previously described
force the conductive pad to be squeezed between the ground block
and the dash panel and establish electrical contact between the
ground block and the bare metal of the dash panel.
[0042] Still another embodiment comprises applying a third type of
special patch to the bare metal of the dash panel in covering
relation to one or more pass-through holes and their margins before
the cab is primed and painted. This third type of patch also
comprises a strippable cover having inner and outer surfaces. The
perimeter margin of the inner surface contains an adhesive for
adhering to the dash panel. The dielectric grease and/or conductive
grease in the two circular areas 20, 22 in FIG. 2 are replaced by
electrically conductive pads that adhere to the bare metal of the
dash panel around margins of the pass-through holes.
[0043] To remove the cover, the edge of a tool (not shown) is
inserted into the dried paint and primer at the edge of the patch
cover and manipulated beneath the margin of the cover sufficiently
to enable further manipulation to pry the cover edge away from the
dash panel. The edge can then be grasped and the cover peeled off.
The electrically conductive pads have less adherence to the cover
than they do to the bare metal of the dash panel, and so they
remain adhered to the dash panel after the cover has been peeled
off.
[0044] With the cover having been removed, the ground block is
mounted on the dash panel as described above.
[0045] While using an adhesive patch or cover to protect an area of
a truck cab from paint is known, the invention is specific to
mounting a ground block on a structural panel by including an
electrically conductive medium in the patch in order to avoid
having to mechanically remove the dried primer and paint in a first
step and thereafter apply dielectric or conductive grease in a
second step.
[0046] While a presently preferred embodiment of the invention has
been illustrated and described, it should be appreciated that
principles of the invention apply to all embodiments falling within
the scope of the following claims.
* * * * *